One of the main tasks in mechanized surface irrigation is to ensure the uniformity of distribution of irrigation norms along the length of the furrow, reducing the limit of discharges and reducing water losses to deep spillage. The magnitude of the technical elements of furrow irrigation is prescribed on the basis of permeability of soils, slope of the field surface, the value of irrigation norms to create the moisture reserves in the calculation of the soil, determining the development of the main mass of the root system of plants and technologies of their cultivation. Discusses various approaches to substantiation of rational elements of the technology of surface irrigation. Most appropriate to address the issue of rational justification of the elements of the technology of surface irrigation are the balance equations. Examples of balance equations based on the theory of infiltration absorption, developed by A.N. Kostyakova. Offered as possible solutions to the form of balance equations of water movement in a furrow and absorption of irrigation norms. It is expected that the dependence will simplify the approach to the assignment of rational parameters of elements of the mechanized watersaving furrow irrigation technology for specific production and economic conditions for ensuring the uniformity of soil moisture along the length of irrigation furrows not less 0.7...0.8 and justify the requirements to the technical means of irrigation.